Acrylic to Glass with Silicone??

[BCOrchidGuy]

I've built my external overflow but am worried about drilling the glass for the bottom of the overflow. I need a 1 3/4 inch hole but the only glass saw is 1 1/4 inch. I could wait till Monday and see if I could buy the bigger hole saw but for only two holes it seems like an extra expense that I could avoid. I've cut the smaller holes and am going to try grinding them out with the rotary tool. If it doesn't work can I silicone acrylic to glass for the overflow and feel secure in it's ability to hold. The acrylic would be 18 inches long by 3 inches wide, 1/4 inch thick siliconed to 1/4 inch glass.
Suggestions? Ideas? Anything?

Doug

[trilinearmipmap]

I have siliconed acrylic to glass to make sump baffles and it worked, however I wouldn't count on if for an application that needs to be strong and watertight.

I have read that acrylic expands by absorbing water, this would throw your seams off. Overall I wouldn't do it.

[adidas]

i had acrylic baffles siliconed to my glass tank..was pretty damn strong.

[fkshiu]

Mixing materials is always a bit iffy. Silicone tends to stick to glass far better than to acrylic.

GE I silicone is "good", GE II is "better" while GE 1200 is the "best" if you can find it. 1200 is what aquarium manufacturers use.

I used 1200 to silicone acrylic baffles to a glass sump and it's watertight, but having to hold up against gravity and water pressure (being an outside pane as I understand your intentions) is another matter.

[BCOrchidGuy]

Thanks for the replies, yes I've got some concerns about the weight of the water, I made the overflow to be about 4 gallons so there is a real concern. I thought about sanding the silicone to give it more surface but I think I'll just head over to Rona and buy another diamond bit and keep cutting.

Thanks again.

Doug

[Tangman]

I think I'll just head over to Rona and buy another diamond bit and keep cutting.


Good idea, acrylic doesn't really bond to silicone any way...